Electric water heater



y. S. LANG @ses Q9 ELECTRIC WATER HEATER w28 2 Sheets-Sheet l Filed`June 4,

TTORNEY @s w, 5 LAN@ HSRQS ELECTRIC WATER HEATER Filed June 4, 1928 2Sheetsheet 2 Neu Patented Dec. 9, 1930 rari-:s

PATENT ori-ice "WALTER S. LANG, OF KENDALLVILLE, INDIANA, ASSIGNOR T()kTHE LANG ELECTRIC MFG'. COMPANY, O? KENDALLVILLE, INDIANA, A CORPORATION0F INDIANA ELECTRIC WATERl HEATER Application led .Tune 4, 1928. SerialNo. 282,698.

ri"his invention relates to improvements in water heaters, and itconsists of the constructions, combinations and arrangements hereindescribed and claimed.

5 f An object of the invention is to provide a water heater having aheating unit in which heating element is made to follow a water pipe, sothat the latter will be subjected to a continuous line of heat.

l Another object of the invention is to provide an electric or gas waterheater having a heating unit comprising a copper or other pipe coil anda helical electrical or gas heat-y ing element interposed between theconvolui tions of the coil so that the latter are subjected directly toa continuous line of heat from the former when active.

i further object of the invention is to provide a novel construction inthe heating unit,

2o permitting removal thereof for repairs from the socalled inside tankor .heating chamber wi hout the need of emptying the main Water tank. y

@ther objects and advantages will appear 235 in the followingspecification, reference being had to the accompanying drawings, inwhich Figure l is a perspective view of the improved water heater,

Figure 2 is a central vertical sect-ion 3G thereof,

Figure 3 is a detail section of the upper end of the heating unit,

Figure 4 is a. detail section of the lower end of the heating unit,

Figure 5 is detail vertical section particularly illustrating thevelectrical terminals 'of the electrical resistance or heating element,

Figure 6 is cross section taken on the line (#43 of Figure 8,"

i9 Figure 'l is a detail perspective view of one of the re 'ractors orinsulating segments,

Figure 8 is a longitudinal section of the thermostat used in connectionwith heater.

Figure i) is a` detail vertical section illusti'ating the adaptation ofa gas helix as the heating element,

l? i gure l() is a detail sectional view of the gas helix.

Although the convenience of hot water and the the need therefor' is feltin every household there are still many of the latter which are notequipped with a modern and ecient water heating apparatus. While it istrue that some residences are equipped with automatic hot water heatersyet it is equally true that the persons in the majority of homes musteither content themselves with the pleasure and convenience of hot wateronly during the winter months when a furnace fire is maintained, ordelegate someone to light the gas water heater when hot water is wantedin the summer.

Inasmuch as the'original cost and the sub'- sequent cost ofmaintenanceof known automatic water heaters is usually high, it is one f ofthe-purposes of the invention to provide a construction which 'willpermit the marketing thereof at a moderate cost, and also one in whichthe cost of electrical current will be low because of the mode in whichthe heat is r while the automatic heater is primarily electrical innature it is also proposed to employ gas 'as the heating medium. Thecommon principle is that of the interpositionofan electrical resistanceor gas helix between the convolutions of a heating coil, so that theheat from either may follow the coil in a continuous line. Y

Reference is made to the drawings. An insulating jacket 1 contains andprotects a main water tank 2, from which it is spaced on all sides,excepting the bottom, thus to insulate the water tank by the volumeofvsurrounding air. A cover 3, of a removable nature pro* vides foraccessto the jacket upon occasion.

Situated within the main water tank is a socalled inside tank or heatingchamber 4 which contains the heating unit seen in Figures 3, 4 or 9. Thetank 2 obviously is intended to contain water which is introduced at acold water inlet 5 and discharged at a hot water outlet 6. The heatingunit is interposed between the two pipes so that the water will beheated to a high temperature on its passage from the inlet to the outletwhen the unit is in action.

The bottom 7 is common to the jacket 1 and main tank 2. The heatingchamber 4 is Vfitted around the rim of an opening 8 in the bottom.Access is thus had to the inside of the heating chamber. As can beunderstood already, the entire heating unit may be withdrawn from theheating chamber 4 without emptying the main tank 2. This is a feature ofgreat convenience should repairs 0r replacements become necessary.

The heating unit comprises a copper or other water pipe 9 shaped into acoil so that a large area may be available as a heatingl surface. Aheating element7 either in the form of an electrical resistance wire 10(Figs. 3 and 4) or a helical gas burner 11 (Figs. 9 and 10), is disposedbetween the convolutions of the coil from one end to the other, so thatthe heat from either element may be applied to the coil in a continuousline. A relatively large coil area is directly affected by the heatingelement so that the water will be quickly raised to a high temperature.

Porcelain or other suitable insulating segments 12 are assembled betweenthe convolum tions of the coil 9 to carry the resistance wire 10. Thesegments have grooves 18 (Fig. 7), collectively forming a` substantiallycontinuous spiral groove when the segments are fitted end to end. intowhich the resistance wire is laid. The groove is sufficiently deepthat'the resistance wire when laying on the bottom cannot touch thecopper coil immediately thereabcve and cause a short circuit.

The resistance element is retained in the groove in spaced relationshipfrom the coil immediately above by lugs 14 (Fig. 7). These lugs areformed on opposite edges of the groove and oppose depressions 15 on theconfronting side of the groove. The depressions make room for pressingthe resistance wire into place in the spiral groove when as sembling theheating unit. The top ot the resistance wire comes slightly below thebottoms of the lugs, thus indicating a sutiicient clearance between thetop of the resistance element and the bottom of the coil immediatelyabove to safely clear the latter.

A close nesting of the insulating segments between the convolutions ofthe coil 9 is obtained by forming concavities 16 in the bottom of thesegments. rlhese concavities receive the upper part of thecoilimmediately beneath. Transverse grooves 1.7 in the bottoms of thesegments 12 admit screws 18 by which the segments are aliixed to theupright bars 19 of an internal cage.

This cage includes and is closed by top and bottom plates 2O and 21,four sides ot cach of which are .flattened as shown in FigA ure 6 topermit screwing the bars in place as at 22. The cage slips inside ot thewater coil 9 and has a tight fit therein. The resistance element isinserted in the grooves oic the segments 12 as the latter are iittedbetween the convolutions of the coil, and as the segments are secured tothe cage the resulting heating assembly constitutes a unit in which thecomponent parts are absolutely tight. The assembly may be inserted intoand removed from the heating chamber 4 as a unit as will presentlyappear.

Copper' rods 23 (Fig. 5) :torni parts ot the terminals of the electricalresistance coil 10. The ends ot the rods are threaded at 24 and 25respectively to screw into insulating bushings 28 at the top, and havebinding posts 2T screwed thereupon at the bottom. Smooth portions of therods pass through bottom insulating bushings Q8, and

.according to the arrangement shown in Figure 5, the screwing up ot thebinding posts 27 will lock the rods and insulators in position upon theinternal cage. The upper and lower ends ot the resistance wire 10 aresuitably secured to the respective rods as indicated at 29 and 30.

The electrical system oit the heater includes the thermostat in Figure8. The fixed and movable contacts 31 and'SQ control an electricalcircuit which embraces the resistance wire 10 and includes a manualswitch 34 by which the current is turned on and ott" when desired. Thethermostat automatically controls the operation ot the heat unit whenthe switch 34 is turned on.

An ebonite rod 35 (Fig. 8) is encased by a copper or other suitable tube3G which is projected into the main water tank 2 so that 'the changes intemperature of the water may affect the ebonite ro l. The inner end ofthe latter is rigidly secured at 37 to a washer or other plug 38 thatseals the corresponding end of the tube. rlhe lett or outer end of thetube is received by and welded at 3i) in one end oit a brass or othernipple 40. The ends ot the nipple are threaded to rcspectively screwinto a brass mounting plate 41 and into a bushing The latter is screwedinto the tank 2, and is suitably packed so that there may be no leakageof water into the insulating space between the jacket and tank.

A centeringwasher has a hole 44 to receive the free and otherwiseunsupported lett end oi the ebonite rod 35. That end carries a contactscrew 45 which may be set at various adjustments by a jam nut 4G. Thescrew 45 co-acts with a similar Contact screw 4'? on a movable fibre barThis bar carries the electrical contact 32, the complementary Contactbeing carried by a Fibre bar 49 fixed upon the mounting plate 41 as at50. hinge block 51 carries the movable bar 48.

It is to be noted in Figure 8 that the inside diameter ot the tube 36 isgreater than the diameter of the ebonite rod, thus making it necessaryto provide the washer 43 in order to keep the ebonite rod in line, andalso keep the contact screws and 47 in line. The Weld at 39 preventsan1J leakage oi' r-Jater around the tube 36.

The principle involved in tho operation of the thermostat is thatebonite has a very high coefficient oif expansion, and since the eboniterod is heleL rigid at the right end ot' the copper tube7 and althouh thecopper tube does expand slightly7 the tar greater expansibility 'ot theebonite rod makes the expansion of the tube negligible so that thedesired operation results.

Any expansion of the ebonite rod will be toward the lett, or in thedirection of its :treedonie Vfhen the heads oi' the contact screws 45and 4:7 meet, any continuing expansion ot he ebonite rod will separatethe electrical contacts 3l and and so automatically open the electriccircuit. Reduction in the teniper'ature ot Water will have the reverseeffect upon the thermostat. rlhe contraction ot the rod 35' will permitthe contacts 3l and 32 to re-engage so that th resistance element l0 isheated again.

Revert-ing to the structure ot the Water heater, the bottom and inletend oit the coil 9 is fitted with a union 52 and a T 53 by whichin'unediate connection is inade With the bott-oni 7 of the Water tank 2.The upper or outlet end of the coil has an elbow 54 (Figs. 2 and 6) intowhich an outlet pipe 55 is screwed. This pige is connected through themedium of a union 56 with the hot Water outl t 6. The hot water outletcou'ununicates be with theftank 2 and With the pipe y A casing 57encloses the exposed' lower end of the heating unit. This casing isreadily removable so tha` 'the heating unit may gotten he heating 'unitis easily reinoree by simply unscrewing the unions and 56 thenrenie-ving either 'the nippleatthe right oi the union 56 or both thenipple and the adjoining elbow, Wl'icreupon the voutlet pipe 55 willpass through the tube 58 when the unit is Withdrawn from the bottoni otthe chamber 1i. A tube 58 surrounds the outlet pipe 55 and closes olfthe tank 2. In Figure 9 this tube 58 will serve the purpose of a tluethrough which the products ot combustion ot the burner ll may escape. ltmay be said in connection rith Figure 9 that the helical gas burner lloccupies the spaces between the conyolutions of thecoil 9 so that theheat from the gas may be Continuously applied throughout the entire.length of the coil. The inixing valve 59 of the gas burner will behoused by the casing 57, and the usual gas cock 60 Will be located onthe outside. A suitable thermostat 6l may be used in both forms of thein- Vention.

The operation is readily understood. It is observed in Fig ure 2 thatthe hot Water outlet 6 has connnunlcation both With the main Water tank2 and.

the outlet pipe 55 of the heating unit, the latter being establishedthrough the branch pipe that carries the union 56. Provision is thusmade for a local circulation of Water as Well as for the flow andinstantaneous heating of the Water as when a faucet is opened.

The local circulation Will occur as long as the heating unit is inoperation, in other Words, as long as the electrical contacts 3l and 32are in engagement and close the circuit through the heating element 10.Hot Water will flow out of the pipe 55 into the top of the tank 2, Whilecooler waterwill enter the bottoni inlet of the coil 9 for the heatingprocess. As soon as the temperatirre of the Water becomes such that theebonitc rod 35 ot the thermostat in Figure 8 is forced to eX- pand asufficient extent, the contacts 3l and will become separated so that theelectrical current is cut off for a time.

Figure 9 does not disclose an automat-ic control of the helical gas coil11, but in practice any known automatic control may be employed. rlhe1principal purpose ot' the modin lic; ion in Figure 9 is to show how gasmay be employed as the heatingyniediuin of the coil 9 as well aselectricity. In order that the principle ot the heating unit may beconiinon in both 'terms of the invention, the gas coil must follow theconvolutions of the Water coil 9 so that there may be a continuous lineot heat against that coil from beginning to end. f

feature that has been emphasized is the eniovability of the heating unitwhether that be adapted for electricity or gas. It is o ly necessary toundo a 'few connections Twhen the entire unit may be abstracted 'treinthe heating chamber 4. By heating unit is meant the Water coil 9 and theheating elenient l() or ll. The ability to withdraw this unit tor themaking of repairs is a great convenience.

It is unnecessary to drain the Water trein the tank 9Jn or in factdisturb anything but the immediate connections to the heating unit. Mostof the heat from the heating elenient will be transferred directly tothe adjacent conyolutions of the coil. 9, but sonne of the radiant heatWill Warin the chamber 4c and tube 58, forming a hot core in thesurrounding volume ot Water.

' While the construction and operation ot tl'e improved Water heater isthat of a generally preferred torni, obviously modifications and changesmay bc inade Without departing troni the spirit ot the invention or thescope oit' the clairns.

I claim 2- l. A water heater comprising a Water tank, a heating unitcomprising a Water coil coniniunicating` at its extremities With thebott om and top of the tank, and a heating elen'ient situated betweenthe convolutions of the coil. and extending troni one extremity to Vthelil() other; and a heating chamber situated within the water tank,containing the heating unit and constituting a hot core for the volumeof water in the tank.

2. A water heater' comprising a w ter tank, a heating unit comprising acoil having an inlet connected with one end of the tank, and an outletpipe, and a heating element located between and following theconvolutions of the coil from the inlet to the outlet; a heating chamberextending from one end of the tank and containing the heating unit, anda tube extending from the heating chamber to the opposite end of thetank encasing the pipe, said chamber and tube constituting` a centralhot core for a volume of water in the tank when the heating unit is inoperation.

3. A water heater comprising a water tank having a bottom with anopening, an inside tank located within the water tank having its wallsfixed around the rim of the opening and having a tube extending to thetop of the water tank, and a heating unit insertable into and removablefrom the inside tank through said opening, comprising a coil with aseparaable connection to one end of the water tank and an outlet pipeconnected with the other end of the tank, situated in the tube andhaving a separable connection with the other end of the coil, and aheating element located between the convolutions of the coil.

4. A water heater` comprising a water tank with a cold water inlet and ahot water outlet, a heating chamber and tube situated within the tankbetween the ends, an outlet pipe contained by the tube being connectedwith the hot water outlet, and a heating unit contained by the heatingchamber, being separably connected with said pipe and one end of thetank, and a heating element incorporated in said unit, being locatedbetween the convolutions of the coil to directly heat the latter,causing a local circulation of water in the absence of a flow from thehot water outlet, and instantaneous heating of the water in the coilwhen there is a flow from the outlet.

5. In an electrical water heater, a heating chamber, and a heating unitcapable of insertion into and abstraction from the heating chamber,comprising a coil, an electrical resistance following the convolutionsof the coil, insulating means by which the resistance is carried, and a.cage fitted up inside of the coil to which the insulating means issecured to complete the unit,

6. In an electrical water heater, a heating chamber, and a separableheating unit located in the chamber comprising a coil, a cage fittedupon the coil, insulating means situated between the convolutions of thecoil, acting as spacers and having a spiral groove, a resistance wirelaid in the groove and serving to heat the convolutions of the coilimmediately thereupon, and means securing said insulating means to thecage forming the unit.

7. In a water heater, a heating chamber, and a heating unit located inbut separable from the chamber, comprising a coil, a cage fitted insideof the coil, a plurality of insulating segments having groovescollectively forming a spiral groove, and having concavities receivingthe coil when located between the convolutions, a resistance wire ofspiral formation laid in the groove, means retaining the Wire in thegroove and preventing contact with the coil, and means to secure thesegments to the cage.

8. In an electrical water heater, a heating chamber, and a heating unitcomprising a coil, a cage fitted inside of the coil consisting of endplates and connecting bars, a plurality of insulating segments havinggrooves collectively forming a spiral groove and having transversegrooves, means extending' through the transverse grooves into connectionwith the bars to secure said elements between the convolutions of thecoil, a resistance wire of helical form laid in the groove and followingthe convolutions of the coil, and terminal connections for saidresistance wire including rods spanning the end plates, bushings fittedin one of the plates in which one end of each rod is secured, bushingsin the other plate through which the other ends of the rods extend, andbinding posts carried by the latter ends.

9, A water heater comprising a water tank with an internal heatingchamber, a heating unit situated in said chamber comprising a coil, andan electrical resistance Wire located between the convolutions of thecoil, and means permitting the disassociation of the heating unit fromthe tank and heating chamber comprising a T and a union connecting oneextremity of the coil with one end of the tank, and a pipe and a unionconnecting the other extremity of the coil with the other end of thetank.

l0. In an electrical heater, a heating chamber open at one end, a fluidcoil, an electrical resistance following the convolutions of the coil,insulating means for said resistance, and means upon which the coil ismounted and to which the insulating means is attached composing aunitary heating element capable of insertion into and removal from theopen end of the heating chamber as a unit.

1l. In an electrical heater, a heating chamber open at one end, a cage,a fluid coil having the convolutions disposed around the cage, and anelectrical resistance having insulating means attached to the cage tospace the convolutions.

12. A water heater comprising a water tank, a chamber extending insidethereof but open to the outside at one end of the tank, a water coil andheating means therefor inserted in the chamber from the open end, andmeans by which immediate connection is made between one end of the coiland one end of the tank constituting the support of one end of the coiland the heating means.

13. A Water heater comprising a Water tank having an inlet and anoutlet, an encased heating unit contained by the Water tank, comprisingheating means and a Water coil having its ends connected incommunication with the Water tank to cause a local circulation in theabsence of a flow at said outlet.

WALTER S. LANG.

